PDF, What is it FOR? - Computerphile
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- เผยแพร่เมื่อ 15 ก.ย. 2016
- Postscript took off like a rocket but PDF took its time, many people wondering "What's it for?" Professor Brailsford's experience with one such person - a US immigration officer...
Unrolling the Loops (Postscript/PDF intro): • Unrolling the Loops - ...
Fire Pong in Detail: • Fire Pong Details - Co...
Deep Dream: • Deep Dream (Google) - ...
FPS & Digital Video: • FPS & Digital Video - ...
Password Cracking: • Password Cracking - Co...
/ computerphile
/ computer_phile
This video was filmed and edited by Sean Riley.
Computer Science at the University of Nottingham: bit.ly/nottscomputer
Computerphile is a sister project to Brady Haran's Numberphile. More at www.bradyharan.com
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This guy is a legend, it seems. The amount of early computer technology this professor was apparently involved in (or in close contact with its creators) is astonishing.
Well it was just a bunch of chaps with ideas back then
Great story, but pity the person waiting in line behind him at the airport that day.
Ikr!
I've just checked how long the section about the immigration person actually lasts on this video. It's about 4 mins. My guess is that it took about half that time for me to explain it on the actual day. But yes I really did explain about Word/Newspapers/AutoCAD in roughly that order. Fortunately it was a relatively "quiet" day in Immigration by SFO standards :-)
ProfDaveB Haha, cool man! :)
ProfDaveB Cheers, Professor. :)
+ProfDaveB
I just want to thank you for all the anecdotes you've shared here on over the years. Awesome and interesting stuff all 'round. :D
Greetings from Denmark.
Professor Brailsford has the best anecdotes on this channel, hands down
Agreed - I love his style - I could listen to him all day talking about his experiences in the industry.
Best storyteller ever.
He held my attention for sure and I could just listen to him for hours I think.
True.
Haha! Showing the user unchecking all the BS spam checkboxes when downloading an Adobe reader update.
Sumatra PDF ftw! :D
lol I just use chrome to read PDFs, much faster and does everything you really need.
Even on a Windows machine i usualy install Evince from the GNOME Project. Works and i need the GTK anyway for Gimp.
can't mark up PDFs in chrome
@@PENDANTturnips i just recently started to trial WPS PDF reader, it is quite nice in fact, it still needs some polishing but some functions like eye protection are much appreciated for us night readers.
I'm just happy we aren't forced to use adobes reader anymore.
Agreed. I find Adobe's reader so clunky and obnoxious.
Official pdf reader is way too big , even without that darn antivirus installer.
if you are sure you only need to view the PDF and not something else such as advanced printing options or Form-Filling features, you can uninstall the adobe reader and uses more lightweight replacement such as SumatraPDF
Agree. I am using Chrome as default PDF reader.
But its the best for touchpad and touchscreen before Edge came in
"What type of business do you do?"
"Tech."
"Welcome to America."
Lol, yea this is exactly how it goes for me . Don't want people in line glaring at me .
PDF was the first enterprise level attempt of a streamlined vulnerability distribution.
what's a vulnerability distribution?
what do you mean with streamlined vulnerability distribution? do you mean that the pdf reader installer was loaded with malware?
oh i thought of it the wrong way lol, yea its the biggest security loophole out there.
they had plenty of competion from Flash, so they had to buy macromedia. ;)
Well, to be fair, they did leave Java for Oracle to but up instead of buying Sun themselves. Monopolies and Mergers and all that :D
This guy is seriously an amazing storyteller. He held my attention the entire time.
5:53 Besides being free, not bundling it with malware also tends to help the adoption rate of software.
But being bundled with malware worked so well for java...
Still does.
the rise of better and also free pdf readers probably helped them a lot.
That, and the widespread ability to export it from third party software like OpenOffice without much hassle. Which does, alas, make it very hard for Adobe to get any money for it...
But if it was free, how did sales out perform Photoshop?
One of the most interesting PDFs I've seen is the Wisconsin e-File form. It does a bunch of things I don't see in other PDF files. The first page has various checkboxes and things to adjust which schedules you want, the number of W2's and other tax situations - once you do that the entire form reconfigures itself to allow you to enter what you indicated. It fills in certain numbers and calculates a few things automatically, and lets you attach additional documents before clicking the button on the form that tells the PDF to itself to the state revenue. -- PDFs can do a LOT more than most people utilize it for.
You could do the same thing with a web page form + Javascript...
@@encycl07pedia- and it's _much_ easier to fill out, read, and process submissions, as well as to edit the form should you need extra requirements.
What a wonderful story.
The one person who downvoted this video works on Floor 4.
2:18 Can we have the 1hour version, only from Professor Brailsford. I'd enjoy it.
Acrobat Reader and PDF files in general felt a lot like the RealPlayer of documents for us mortal people who just wanted to look through a manual or a brochure online.
Praise PDF.js
PDF's could be exploited to run code, as well as execute completely unrestricted javascript. I think those exploits are all but gone these days, but vulnerable installers are still found on many driver cd's, and people still to this day fall victim.
Don't most browsers integrate a PDF reader these days? I'm a bit sheltered - I use a Mac, so PDF is written into its OS as its underlying graphics model, so it handles PDF as a native type (indeed it uses it for internal representation of any graphic content, even for things like cut-and-paste). So 'Acrobat' simply isn't a thing on the Mac (it exists, but I'm not sure what it does that you can't do with the OS anyway). Writing a PDF reader on the Mac takes just a few lines of code. But I assume that Windows handles it reasonably well also, otherwise it would never have taken off.
@@GRAHAMAUS Firefox uses PDF.js, which converts PDF to HTML, so you can even inspect elements within the document.
Oh wow, I had forgotten RealPlayer.
I'm so thankful for PDF. Its easy to work with, I don't worry about it having any problem displaying for anyone. If I send someone a pdf, I know what they received, and that they should be able to open it on just about anything they are using. Truly an underrated program that is used so commonly.
I never really appreciated just how great PDF was until I worked on a full rebrand for a premium horse feed company, digital, print, packaging, uniforms. To be able to have that universal format that worked in every step of the process with certainty was amazing.
First time I saw a PDF displayed on-screen was at a electronic engineer's place. The data sheet was in that newfangled PD format, and it just looked beautiful: drawings, text, tables, diagrams, all smooth and crisp at the same time, because they all were rasterised with anti-aliasing. I was hooked and ordered my first CD-based archive of some monthly computer magazine right away.
I've seen some very bad full justification in my day, even though I don't own an e-book reader, but what you forced onto my retina at 3:17 is a whole new kind of evil.
+Penny Lane Adobe After Effects sends its regards....
This is *high quality* bad justification.
***** Then I think I'd prefer the Lannisters.
***** How would you convince someone of such nonsense?
Penny Lane Honestly, I believe that it is part of the national standards for written works where I live.
Teachers want to see full justification even if of bad quality over any well done left justification. And then students grow with the idea that left justification is bad.
Idk, Is left justification regarded as bad? I'm afraid you will tell me that left justification is worst, but I'm unsure if that's my indoctrination talking.
Loved that passport story!
The funniest part is that Acrobat Reader these days is way worse than free alternatives. They consistently get encoding wrong, so I've been forced to use Sumatra to get the encoding right in my documents.
Also 88mb to download adobe vs 5mb for sumatra. Makes you wonder wtf else comes with that adobe installer
+Ardulogger PDF is just an awful format. Implementing all the features apparently requires that many megabytes.
People don't make PDFs properly, if they did you would not have any issues.
why not create alternative format to pdf for example
Gzip +image ...
@@ioijiopjkiopjkp xpdf on Linux and BSD's: 2.1Mb.
How does prof Brailsford know so many massively influential people in the industry?
The truthful answer is probably " ... because of typesetting and Document Engineering". In the very early (early 80s) days I met Brian Kernighan because of a common interest in typesetting (see "202 Jailbreak"). At the tail end of the 202 era the possibility of proofing our stuff on a brand new PostScript laserwriter led me to start a journal called "Electronic Publishing" which used
exclusively PostScript to typeset its articles and this PostScript was then archived. John and Chuck of Adobe got to hear about this and let us in early on the Acrobat/PDF scene. And so on.
Once you know a couple you get introduced to others, who introduce you to others... it's a snowball effect.
+ProfDaveB - my hat is off to you
He is one of them...
I imagine it's a bit like the Casino industry it's a small industry but unique and it seems everyone knows everyone else. I've met people from Japan, Australia, US, Monte Carlo, Austria, Morocco and I'm just in small town Canada.
That's easy. PDF are just media files that are designed with all content contained inside the file, with security to stop people from changing the information easily. Also as important was the ability for the PDF to look the same everywhere, to everyone.
When I first learned how to write my own PDFs it felt amazing. Then again this was back 15 - 20 years.
"security"
The only security was that the editor cost money, while there the viewer-reader was free. For crying out loud, PDF is not meant to be used for documents "not to be changed", it is meant to communicate documents where layout preservation is important. All other use cases are wrong format usage and cause more problems than they solve.
I remember joining the Microchip BBS some time in the early 90s and they had posted electronic copies of datasheets but we couldn't read them. I think they were in some private DTP format back then. I'm not sure what year Microchip adopted PDF.
I believe it was a game changer in electronics.
Also my explanation was that PDF was "like printing it out for someone to read except you get a file instead of paper."
as late as mid-2003 the instructors at my college didn't know what to do with my PDF assignment submissions. I developed the habit of producing a rich text and PDF copy of each paper, because so many instructors insisted that rich text was fine. every single time they ended up using the PDF to grade my work because the rich text turned to garbage on their computer (most of which I had installed and maintained perviously when I worked for the college's IT dept... so I knew what to expect) and I knew they used the PDFs because they'd email me asking how to open them.
Wait, these were instructors in the computing fields?!
Very informative, thank you. I guess I hadn't really thought about it, and in hindsight it seems obvious, but before this I didn't really understand what PDF was for. I love learning things, so thanks again. :)
This man is a pleasure to listen to... I'd love to have professors like him back in the day.
I love your videos, professor. I am roughly your age so I lived through a lot of the history of computer science that you describe. It really brings back memories to hear you talk about it.
Thanks.
Thanks! Since the demographic of Computerphile peaks with people much younger than we are,it's nice to get a "thumbs up" from a fellow oldie
Honestly, I could not imagine doing research without LaTeX / pdf files. I use it for articles, presentations, notes... Seriously everything I send people uses pdf.
ever heard of html? it's pretty great! ;)
sofias. orange People use HTML for articles? That's crazy!
LeiosOS well they should, anyway. :P in my experience it's still slightly lacking in print capabilities, and columns are still not working that well (interestingly Edge does a good job here).
but when it comes to presentations, there are some *really* great html solutions out there. i did a presentation in svg once. very much like prezi. unfortunately it completely broke on the browser of the presentation machine (only tested it on mine) and the text was completely unreadable. ^^; probably would work fine now, tho :P
Nah, not that crazy anymore. It is super flexible. You can achieve so much more these days with web technologies than you can with PDF. Virtually every device has a web browser available, and not only can you display web pages on very different devices, you can also make specific adjustments to optimize pages for say different screen resolutions (and yes, also for print). Inconsistencies across browsers are becoming less and less of an issue. HTML also provides the text data in a structured form, which is one of the big, big shortcomings of PDF. Ever tried to copy and paste from a PDF and got a completely chopped mess? And PDF is just a nightmare if you want to include multimedia content such as Videos. Video, audio, animations all work beautifully and consistently (if done right) in HTML5, which is very nice for presentations. The only real advantage that PDF holds today is that it allows perfect reproduction of documents, which is is essential for the print industry.
What he describes with architectural drawing couldn't be more right. I used to have to program macros to get the plot to look just right and it was an absolute nightmare between machines. Until we realized we could just always print it digitally as a pdf and then print that as a paper document, we could NEVER get repeatable results. Don't get me wrong, it was passable but for whatever reason, you could never get uniformity with AutoCAD even if you installed the same version, same fonts, etc. on a different machine. The plots were always different, especially with a different printer. I honestly thought it was kind of bloatware until I needed it and then came to realize what a godsend it was.
PDF is especially useful for sheet music, where each note, dot, line slur has to be at its exact place. I wonder how they do this!
Absolute positioning
It's all PostScript behind the scenes, using vector image formats.
I always thought that PDF was a PITA because I only had experience with receiving documents that could more easily have been sent as a Word file. Just recently I received a set of model yacht plans in PDF that had to be printed at about A1 size. It opened my eyes to a whole new world. I could look at the plan on my screen. I could take the .pdf file to the local printing shop and have it printed full size. The scale bar on the print was exactly the size it was meant to be. The print looked exactly like it did on my screen.
Professor Brailsford I thank you for your explanation that has tied everything together and the penny has now dropped. For my purposes .pdf is still not the best for documents, but it is a fantastic format for drawings, plans, etc. I hope never again to expand drawings, put them on A4 and sticky tape them together. Thank you.
I think your issue is that you need a bigger printer. It's nothing to do with the file format.
He tells the best stories. I could listen to him for hours.
10 seconds in and already liked it, I love this mans storytelling, must be a great teacher :)
That was an incredibly well told story. MORE from this guy please!
Ah, the days when immigration personnel actually had brains...
I can watch this guy talk for hours! He should start a weekly podcast.
PDF is by far one of my favorite file types to view, it's absolutely fascinating.
I truly loved this for the story, I love these videos
I asked this question before myself but quickly learned how it was useful for me in business. This was an interesting and informative story.
As a pro typesetting and graphics company in the 1990 era we were extremely keen on the idea of PDF, but it had a persistent problem for quite a long time with white type and white lines which disappeared as though they were not there at all. Acrobat has been amazing, but annoying with many updates that seemed to us to be worse or with less functionality than the older versions, especially as we used Pitstop with it as well.
Come to think of it, is there any aspect of computing history that Professor Brailsford was not a part of?
he didn't know Charles Babbage and Ada Lovelace, i think.
You can't be sure, though
He is a genius, so I assume he has part in every great achievements.
I don't think he was involved in general recursive functions.
Never someone recognized the divergence between a 'working document' and a 'presentation document'.
Word format and such are 'working document' not a finished product, PDF is!
Except PDFs aren't all 'finished' !
I get asked that also quite often I usually reply: pdf is like the digital version of printing a document in paper, you are supposed to use it for reading and sharing but not for editing it.
How do I get a PDF file under my flatbed scanner ?
So why does every lease agreement ever come as a pdf and I have to input the fields if it's not meant to be edited
@@csmlyly5736 Just to make life difficult
I think the problem with pdf was acrobat reader. That program caused me so much grief in the past, and was always trying to install updates. Moving to mac and using Preview made my enjoyment of the pdf format increase exponentially.
I love hearing about the history of computing like this, even when it's not all that old.
Its for hiding exploits and delivering them to the unsuspecting, a task it excels at.
And as a kid growing up with PDF files already in use, it's easy to not realize how freaking revolutionary that was. And the reasons he describes are the very reasons I had acrobat reader, to look at & print documents (for free).
Great Story! I could listen to this gentleman talk all day!
I really love this guy, always has a great story.
Thank you so much for your videos! This channel is such a wealth of knowledge :D
So cool, i love to hear stories!
Need MORE Professor Brailsford please!
Didn’t he pass away last week?
@@unnamedchannel1237
Wait what‽
Secondly pls check the date of commenting
PDF is a document format just like any other. The only difference is that Adobe does not feel it is cool to change how it works for every release like Microsoft does.
I worked for a company that thought that they should use PDF because they thought you couldn't edit it. Sigh.
They thought you what? WHAT!?
It has happened to me too, many, too many times already....:(
I'm Jack's Nipples
Hehe. Don't believe everything you read on the Internet, kid!
Very rarely use actual Acrobat Reader but PDF is a truly great format. I use it as a kind of paperless paper for documents. The one thing I hate, though, is when forms are simply "copied" to this format rather than being the machine completable things the format is capable of doing. I am no good at handwritten form completion and frequently find myself using something like Xournal and a modified "monospace with thin spaces" font to overlay text onto such forms.
Why use PDF for docs ? Surely 'paperless docs' = html ?
what a nice story, worth every minute of it!
I remember well during mid and late 90's that you couldn't create a PDF document for free. The acrobat PDF reader was free but the office plugin for converting word documents to PDF wasn't free at all. Only afterwards and especially with OpenOffice it became free.
Well you sure gave a much better explanation of what pdf was about compared to Adobe. It was basically take it or leave it when I asked them. Given that Adobe love applying the Australia Tax, I left it.
What a quirky little story about how PDF became the norm for document transfer, and how it nearly didn't happen. I relate to this because of my own early experiences with Acrobat PDF back in 1995'6 when I was briefly working at Fineline Design & Print in Hungerford. Oh the joys of trying to open, edit and save PDF back then in its infancy. I remember hating it. Now it's excellent and easy to use. Any way this made me smile.
"Post script", "Word Perfect", the 1980's... ah, the memories. Thanks for sharing!
Absolutely great video.
5:55 first untick McAffee, untick True Key... THEN install :p
oh wow the first 4 comments are people listing their position and they are in the correct order, what madness is this?
never seen that before.
I'd love to see some more videos about PDF. It is easily one of the greatest protocols/formats ever made in the history of computers.
Completely wrong.
Great storytelling and history lesson
These history ones are really interesting!
In my opinion the point seems to be the go-to for WYSIWYG if you do desktop publishing. Can do stuff like embed fonts, vector images (raster images can still go pixelated unless high-res, sorry), and assign spot colors. If you're just editing documents and continuously revising, not so much. But for final output with intent of printing it, then yeah.
As always, a very pleasant and entertaining look into the history if IT. :) I wonder if people needed to reverse reverse engineer the PDF format to make open source libraries for writing it, like it was with Word, or if Adobe gave the specs away at a certain point.
The standard is largely open and free now.
It’s clear one of the design goals for PDF was that it would be easy to print on PostScript printers -- basically you prefix a PostScript prelude to define those one- or two-character PDF operators as synonyms for their direct PostScript equivalents, then send the contents of the page as is, end with a “showpage”, and out it comes.
It seems in the beginning they couldn’t quite decide whether PDF would be a text or a binary format. They soon realized, of course, that conversions between differing OS-specific line-ending conventions would corrupt the object table if a PDF file was treated as text, so they added a recommendation (which might still be in the spec) that PDF generators include some random binary garbage near the start of the file, to stop format sniffers from concluding that they were dealing with a text file.
Thank you, this is a very good story.
Back in the 90s I always got so upset when somebody had made a PDF out of some simple text file. What was a 10kB download suddenly ballooned to 5MB, in the days of ~4kB/s downloads. It was the difference between "instant" and "go get a sandwich, then eat it, and maybe it'll be done by then".
Most of the time, it was totally unnecessary. Whoever did it did so because they thought it looked nicer, or more professional, or just that they were supposed to do that. I'm not sure I ever ran into a legitimate use of PDFs until I was an adult.
Hey, professor, we were WordPerfect refuseniks for a very good reason: "Reveal Codes" was the most useful feature on the face of the earth.
Was that a DOS WP ? I don't think I ever saw it as a DOS prog.
No other word processor had a “Reveal Codes” function because no other word processor used embedded codes for formatting.
Yay, a computerphile video that a non-programming /non-computer expert like me can understand!!
I'm from that background so maybe I don't see it but I was under the impression that most of the time they are pretty good at putting things in layman's terms. Some of the so and image codec videos are a bit heavier though.
TheSpacecraftX Sometimes they are. I wouldn't call myself completely computer illiterate (I'm quite confident using them to do everything I need to do), but I don't have any clue about the underlying mechanics or programming of hardware and software etc. That just goes over my head.
I like the computerphile videos that are about computer-related topics I can understand on a practical level (e.g. the history of PDFs, how to use programs programs, the importance of password security etc.) or are of theoretical interest like the ones on artificial intelligence or electronic voting that don't require me to understand the minutiae.
Same goes with numberphile to be honest. It used to be fun facts and trivia about numbers and mathematical patterns or riddles, but now it is a bit hard-core for me.
Great story! :) thank you for sharing
Great video, thanks!
In the mid-90s I worked for a company who did hardware and software for the printing industry. We ate, lived and breathed PostScript.
One product we did was a PostScript sanitizer to take the weird PostScript some applications generated and make it more suitable for further processing. The sort of thing we dealt with was code that said "0 setlinewidth". This gave a minimum thickness line on paper at 300 dpi (OK), but nothing on a 2400 dpi printing plate (not OK).
One of the tools we used was Acrobat. Read bizarre PostScript, turn it in to (very early) PDF, write nice clean PostScript from the PDF.
Nice story -- and an ingenious way to exert quality control on variable-quality incoming PostScript.
What a charming fellow and a great story
A very interesting episode.
What an awesome story teller
Fantastic story!
I didn't know much of that either. So thanks.
I would love to hear Prof Brailsford's thoughts (if any) on OpenXPS.
This guy is such a brilliant mind and a truly wonderful storyteller. Here's an interesting question - do you reckon in fifty years time there will be similar videos with some elderly distinguished professor telling us about how they first developed TikTok? 😛
What a great video!
When i was an art student I know we were interested in PDFs because it allowed you to bake in fonts and your graphic over/under lays and reduce file size.
I remember Unix people would just offer Postscript files for interchange, which we could make quite easily with TeX and troff/groff. PDF really is just an extension of that, the transformation from PS to PDF is both straightforward and reversible. Which of course Brailsford would know all about, lol.
David, you could even COUNT and I would still watch you with big PLEASURE ;-)
I vaguely remember that when I was a student in a university in the early/mid 90's, Postscript was something like a "no, unless you pay for it" and then there were dubious workarounds like Ghostscript and alike that allowed poor students to do some high quality printings of some documents that were in PS. But I cannot remember how PDF entered the scene. It must have been a quite big thing for a computer enthusiast like me, but I just do not have specific memories about it from those early days.
Look at that like to dislike ratio, that's pretty damn good.
divide by 0 error...
Segmentation fault.
Allri-- **turns into 8 sideways**
Dud you jinx it.
This video made me think of a word document I had to send in.. the deadline was yesterday.... Why couldn't this video be in my recommended feed yesterday 😫
I remember when PDF came out. I was very familiar with all those format compatibility problems, and PDF was a godsend for document exchange.
Wasn't that the point of RTF ?
Professor Brailsford
How exactly does pdf make money for Adobe?
Adobe reader is free, but Acrobat (the editor), costs a fortune.
how ??? the acrobat ??? costs??
that, and hoping that people will not notice the spamware included in the installer
Reader is free, but the editor costs money (adobe acrobat at least, there are free editors though).
***** how ?? if those r free then how money ???
I remember wondering why it was called "portable" while (initially) only being supported on Windows and Mac, and not the OS that I was using. Had you called it "Printable Document Format" I would have understood its strength right away.
(Of course, these days it's supported quite well.)
The 50 frames per second has such a neat look to it
It's always interesting how technology and standards that we take for granted today came to be.
Saw it only for the first 10 seconds but leads me to the statement: What a great guy.
Thank you for explaining that to me other sites did badly
nicely told story
I wish I could hangout with Professor Brailsford for a day!
This is so elaborated dear lord
I would of said it's like having a piece of electronic paper that you can see and looks the same whether it's viewed on a MAC, PC or anything else. You can mark in up with a virtual pen or pencil, add notes and virtual sign it (if need be) and send it to someone else who can see it exactly the same on his computer and counter sign it (if need be), basically paper without the paper.